Patent Literature (PTL) 1 discloses an antenna which is installed on a portable image display device and has improved radiation directivity. This antenna includes a radiating element and a parasitic element that is provided near the radiating element at a distance of 0.25 wavelength or less, and thus can exhibit a directivity pattern with low directivity.
PTL 2 discloses a technique for improving the isolation between antennas of two wireless terminals by providing a notch in a conductive layer formed on an inner surface of a housing in which both the antennas are arranged. An electric current that flows between both the antennas through the conductive layer is reduced by the notch, and thus the isolation between both the antennas is improved.